Former Bosnian Serb military chief Ratko Mladic has made his first appearance before the U.N. war crimes tribunal at The Hague, but refused to enter a plea to what he said are "obnoxious" charges of genocide against him.

Mladic told the court's three judges on Friday that he was defending "my people and my country" during the fighting in the 1990s that splintered the one-time country of Yugoslavia. He said he needed "more than a month" to read the "monstrous words" in the indictment. Mladic is accused of masterminding the 1995 Srebrenica massacre of 8,000 Muslim men and boys - Europe's worst mass killing since World War II - and the 44-month siege of Bosnia's capital Sarajevo in which 10,000 died.

Alternately subdued and feisty, Mladic told the court he did not want "a single letter or sentence" of the indictment read in court. But Presiding Judge Alphons Orie ignored the request and read all 11 charges against Mladic.

The 68-year-old Mladic told the court he is "gravely ill," but also asked for the hearing to go into private session so he could discuss his health with the judges without a worldwide television audience hearing the conversation. Back in open court, the somewhat frail Mladic pointedly said he did not want guards helping him to walk unless he asked for assistance.

Orie set July 4 for Mladic's next hearing, when Mladic will be required to offer a plea to the charges. If he does not, an automatic not-guilty plea will be entered on his behalf.

He was once a burly, intimidating figure on the battlefield. But Mladic, wearing a light gray suit, appeared somber as Orie read the charges against him.

Mladic said he had not read the indictment and needed "a bit more time" to think about the allegations. If convicted, he faces life imprisonment.

He has been at The Hague since Tuesday after being flown there from Serbia where he was arrested last week.

In advance of the hearing, his court-appointed attorney, Aleksandar Aleksic, said Mladic has not had proper health care for years. Aleksic said Mladic spent Thursday night in a prison hospital, but the tribunal said Mladic's medical supervision was routine.

The lawyer said he would ask the war crimes tribunal to approve more medical tests for his 69-year-old client. The exact state of Mladic's health sparked a dispute when another of his attorneys, Milos Saljic, said he has a document claiming that Mladic suffered from lymph node cancer and underwent surgery for it in 2009.

But a Serbian prosecutor, Bruno Vekaric, said the document "looks like a hoax."